Add Google reCAPTCHA v3 to CF7

Integrates Google reCAPTCHA v3 with Contact Form 7

PHP

function add_recaptcha_v3() {
    ?>
    <script src="https://www.google.com/recaptcha/api.js?render=YOUR_SITE_KEY"></script>
    <script>
    grecaptcha.ready(function() {
        grecaptcha.execute('YOUR_SITE_KEY', {action: 'contact'}).then(function(token) {
            var forms = document.getElementsByTagName('form');
            for (var i = 0; i < forms.length; i++) {
                var input = document.createElement('input');
                input.type = 'hidden';
                input.name = 'g-recaptcha-response';
                input.value = token;
                forms[i].appendChild(input);
            }
        });
    });
    </script>
    <?php
}
add_action('wp_footer', 'add_recaptcha_v3');